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991.
N S Sergeeva M Iu Vasil'ev T I Kovalenko N V Sokolova G I Avdeev 《Eksperimental?nai?a onkologii?a》1989,11(2):35-37
The indirect immunofluorescent technique was used to study the distribution of the ascitic fluid antigen (AgD) on histological sections from surgical specimens of gastric and colon tumours from proximal to distal lines of resection. AgD was found in gastric tumours exceptionally in the tumour area and in colon cancer--both in the tumour stroma and in surrounding histologically normal mucosa. 相似文献
992.
V. V. Skorokhod N. K. Prokushev I. O. Shmatko 《Powder Metallurgy and Metal Ceramics》1987,26(11):875-880
Conclusions A method is proposed making it possible to study the high-temperature kinetics of the variation of the coefficients of shear ductility of a porous solid and its material during sintering under pressure. An investigation was carried out into the variation of the ductility of copper powder compacts in the temperature range 700–950°C. Experimental data are compared with results obtained on the basis of the theory of diffusion-viscous flow and a general rheological theory of sintering. It has been established that in the initial stage of sintering at 950°C the coefficient of shear ductility of copper increases linearly with time. Under conditions of diffusion-viscous flow of a polycrystalline material, this is due to diffusional grain growth according to a parabolic law. It is shown that experimental values of shear ductility of copper are smaller than values obtained on the basis of the rheological theory of sintering. Values approximating most closely to experimental data have been obtained with a model of an ideal porous solid.Translated from Poroshkovaya Metallurgiya, No. 11(299), pp. 11–17, November, 1987. 相似文献
993.
Yu. V. Drobyshevskii V. K. Ezhov E. A. Lobikov V. N. Prusakov V. F. Serik V. B. Sokolov 《Atomic Energy》2002,93(1):578-588
The exploding-wire method, the photochemical method of irradiation with a light flux from a high-pressure mercury lamp, a high-intensity spark discharge, and irradiation by a CO2 laser are used to reduce plutonium hexafluoride and to separate it from uranium hexafluoride. The dependence of the reduction of plutonium hexafluoride on the wire material, the mass of the reduced product, and the amount of input energy is investigated.It is shown that the methods presented for reducing plutonium hexafluoride and separating it from uranium hexafluoride can be used under static and dynamic conditions for preparative purposes and on a large scale. 相似文献
994.
The optimum procedures for synthesis of UO2CO3 and Na4[UO2(CO3)3] were developed. The structures of these compounds and their thermal decomposition were studied by X-ray diffraction, precision IR spectroscopy, and thermography. The standard enthalpy of formation of crystalline Na4[UO2(CO3)3] at 298.16 K was determined to be -4010.0±8.0 kJ mol-
1. 相似文献
995.
In this paper, we propose an approach that combines the unsupervised and supervised learning techniques for unconstrained
handwritten numeral recognition. This approach uses the Kohonen self-organizing neural network for data classification in
the first stage and the learning vector quantization (LVQ) model in the second stage to improve classification accuracy. The
combined architecture performs better than the Kohonen self-organizing map alone. In the proposed approach, the collection
of centroids at different phases of training plays a vital role in the performance of the recognition system. Four experiments
have been conducted and experimental results show that the collection of centroids in the middle of the training gives high
performance in terms of speed and accuracy. The systems developed also resolve the confusion between handwritten numerals. 相似文献
996.
997.
Wakabayashi H. Ueki M. Narihiro M. Fukai T. Ikezawa N. Matsuda T. Yoshida K. Takeuchi K. Ochiai Y. Mogami T. Kunio T. 《Electron Devices, IEEE Transactions on》2002,49(1):89-95
Sub-50-nm CMOS devices are investigated using steep halo and shallow source/drain extensions. By using a high-ramp-rate spike annealing (HRR-SA) process and high-dose halo, 45-nm CMOS devices are fabricated with drive currents of 650 and 300 μA/μm for an off current of less than 10 nA/μm at 1.2 V with Toxinv =2.5 nm. For an off current less than 300 nA/μm, 33-nm pMOSFETs have a high drive current of 400 uA/μm. Short-channel effect and reverse short-channel effect are suppressed simultaneously by using the HRR-SA process to activate a source/drain extension (SDE) after forming a deep source/drain (S/D). This process sequence is defined as a reverse-order S/D (R-S/D) formation. By using this formation, 24-nm nMOSFETs are achieved with a high drive current of 800 μA/μm for an off current of less than 300 μA/μm at 1.2 V. This high drive current might be a result of a steep halo structure reducing the spreading resistance of source/drain extensions 相似文献
998.
999.
1000.
S. M. Fitzpatrick D. Miller I. Weatherston J. N. McNeil 《Journal of chemical ecology》1985,11(2):207-215
Levels of benzaldehyde recovered from virginPseudaletia unipuncta (Haw.) males were not influenced by (1) the time hairpencils remained in the solvent (1-72 hr), (2) anesthetization or agitation of males prior to excision of hairpencils, or (3) the time (photophase or scotophase) that hairpencils were excised. Thus the interindividual variability observed is not a methodological artifact. Most males had similar concentrations in both hairpencils, although in some cases only one hairpencil contained pheromone. In one case, a male with partially extruded hairpencils had no benzaldehyde at all. Neither pupal weight nor hairpencil length proved to be reliable indicators of pheromone content.Contribution No. 373, Département de biologie, Université Laval. 相似文献